Add support for user defined "pool" to GN.

tools/gn/ninja_build_writer.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "tools/gn/ninja_build_writer.h"
 
 #include <stddef.h>
 
 #include <fstream>
 #include <map>
 #include <sstream>
 
 #include "base/command_line.h"
 #include "base/files/file_util.h"
 #include "base/path_service.h"
 #include "base/process/process_handle.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "build/build_config.h"
 #include "tools/gn/build_settings.h"
 #include "tools/gn/err.h"
 #include "tools/gn/escape.h"
 #include "tools/gn/filesystem_utils.h"
 #include "tools/gn/input_file_manager.h"
 #include "tools/gn/ninja_utils.h"
+#include "tools/gn/pool.h"
 #include "tools/gn/scheduler.h"
 #include "tools/gn/switches.h"
 #include "tools/gn/target.h"
 #include "tools/gn/trace.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #endif
 
 namespace {
@@ skipping 86 matching lines @@
   return result;
 }
 
 }  // namespace
 
 NinjaBuildWriter::NinjaBuildWriter(
     const BuildSettings* build_settings,
     const std::vector<const Settings*>& all_settings,
     const Toolchain* default_toolchain,
     const std::vector<const Target*>& default_toolchain_targets,
+    const std::vector<const Pool*>& all_pools,
     std::ostream& out,
     std::ostream& dep_out)
     : build_settings_(build_settings),
       all_settings_(all_settings),
       default_toolchain_(default_toolchain),
       default_toolchain_targets_(default_toolchain_targets),
+      all_pools_(all_pools),
       out_(out),
       dep_out_(dep_out),
       path_output_(build_settings->build_dir(),
-                   build_settings->root_path_utf8(), ESCAPE_NINJA) {
-}
+                   build_settings->root_path_utf8(),
+                   ESCAPE_NINJA) {}
 
 NinjaBuildWriter::~NinjaBuildWriter() {
 }
 
 bool NinjaBuildWriter::Run(Err* err) {
   WriteNinjaRules();
-  WriteLinkPool();
+  WriteAllPools();
   WriteSubninjas();
   return WritePhonyAndAllRules(err);
 }
 
 // static
 bool NinjaBuildWriter::RunAndWriteFile(
     const BuildSettings* build_settings,
     const std::vector<const Settings*>& all_settings,
     const Toolchain* default_toolchain,
     const std::vector<const Target*>& default_toolchain_targets,
+    const std::vector<const Pool*>& all_pools,
     Err* err) {
   ScopedTrace trace(TraceItem::TRACE_FILE_WRITE, "build.ninja");
 
   std::stringstream file;
   std::stringstream depfile;
   NinjaBuildWriter gen(build_settings, all_settings, default_toolchain,
-                       default_toolchain_targets, file, depfile);
+                       default_toolchain_targets, all_pools, file, depfile);
   if (!gen.Run(err))
     return false;
 
   // Unconditionally write the build.ninja. Ninja's build-out-of-date checking
   // will re-run GN when any build input is newer than build.ninja, so any time
   // the build is updated, build.ninja's timestamp needs to updated also, even
   // if the contents haven't been changed.
   base::FilePath ninja_file_name(build_settings->GetFullPath(
       SourceFile(build_settings->build_dir().value() + "build.ninja")));
   base::CreateDirectory(ninja_file_name.DirName());
@@ skipping 40 matching lines @@
   // Additionally, remove duplicate filepaths that seem to creep in.
   std::set<base::FilePath> fileset(input_files.begin(), input_files.end());
   fileset.insert(other_files.begin(), other_files.end());
 
   for (const auto& other_file : fileset)
     dep_out_ << " " << FilePathToUTF8(other_file);
 
   out_ << std::endl;
 }
 
-void NinjaBuildWriter::WriteLinkPool() {
+void NinjaBuildWriter::WriteAllPools() {
   out_ << "pool link_pool\n"
        << "  depth = " << default_toolchain_->concurrent_links() << std::endl
        << std::endl;
+
+  for (const Pool* pool : all_pools_) {
+    std::string pool_name = pool->GetNinjaName(default_toolchain_->label());
+    out_ << "pool " << pool_name << std::endl
+         << "  depth = " << pool->depth() << std::endl
+         << std::endl;
+  }
 }
 
 void NinjaBuildWriter::WriteSubninjas() {
   for (const auto& elem : all_settings_) {
     out_ << "subninja ";
     path_output_.WriteFile(out_, GetNinjaFileForToolchain(elem));
     out_ << std::endl;
   }
   out_ << std::endl;
 }
@@ skipping 162 matching lines @@
   EscapeOptions ninja_escape;
   ninja_escape.mode = ESCAPE_NINJA;
 
   // Escape for special chars Ninja will handle.
   std::string escaped = EscapeString(phony_name, ninja_escape, nullptr);
 
   out_ << "build " << escaped << ": phony ";
   path_output_.WriteFile(out_, target->dependency_output_file());
   out_ << std::endl;
 }